1. Field of the Invention
The present invention relates to an electromagnetic fuel injection valve for use in an internal-combustion engine. More particularly, the present invention relates to an electromagnetic fuel injection valve wherein it is possible to prevent undesired adhesion between the respective abutting surfaces of an armature and a stationary core as well as to improve wear resistance of the two abutting surfaces.
2. Discussion of Related Art
A typical electromagnetic fuel injection valve has an electromagnetic coil and a valving element secured to an armature. In operation, the electromagnetic coil is excited to lift the armature. When the armature thus lifted abuts against a stationary core, a gap is created between the valving element and the associated valve seat, thereby allowing fuel to be injected through the gap. Accordingly, it is necessary to ensure wear resistance for the respective abutting surfaces of the armature and the stationary core and to eliminate or minimize residual magnetism between the abutting surfaces. It has already been known that at least one of the two abutting surfaces is plated with chromium or nickel to ensure the required wear resistance and to eliminate or minimize the residual magnetism (for example, see Published Japanese Translation of PCT International Publication No. Hei 8-506876).